Refined GitHub - Browser extension that makes GitHub cleaner & more powerful
Commit Together by Github - Now add co-authors to your commits
Octoview - The missing preview feature for GitHub
Commit Print - Posters of your git history
Dyllo - A clean and simple way to view a Github user's information
Macarons - Macarons is your virtual watercooler for casual conversations with colleagues you rarely meet on the hallway.